1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* This Source Code Form is subject to the terms of the Mozilla Public 3 * License, v. 2.0. If a copy of the MPL was not distributed with this 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 5 6 #ifndef prclist_h___ 7 #define prclist_h___ 8 9 #include "prtypes.h" 10 11 typedef struct PRCListStr PRCList; 12 13 /* 14 ** Circular linked list 15 */ 16 struct PRCListStr { 17 PRCList *next; 18 PRCList *prev; 19 }; 20 21 /* 22 ** Insert element "_e" into the list, before "_l". 23 */ 24 #define PR_INSERT_BEFORE(_e,_l) \ 25 PR_BEGIN_MACRO \ 26 (_e)->next = (_l); \ 27 (_e)->prev = (_l)->prev; \ 28 (_l)->prev->next = (_e); \ 29 (_l)->prev = (_e); \ 30 PR_END_MACRO 31 32 /* 33 ** Insert element "_e" into the list, after "_l". 34 */ 35 #define PR_INSERT_AFTER(_e,_l) \ 36 PR_BEGIN_MACRO \ 37 (_e)->next = (_l)->next; \ 38 (_e)->prev = (_l); \ 39 (_l)->next->prev = (_e); \ 40 (_l)->next = (_e); \ 41 PR_END_MACRO 42 43 /* 44 ** Return the element following element "_e" 45 */ 46 #define PR_NEXT_LINK(_e) \ 47 ((_e)->next) 48 /* 49 ** Return the element preceding element "_e" 50 */ 51 #define PR_PREV_LINK(_e) \ 52 ((_e)->prev) 53 54 /* 55 ** Append an element "_e" to the end of the list "_l" 56 */ 57 #define PR_APPEND_LINK(_e,_l) PR_INSERT_BEFORE(_e,_l) 58 59 /* 60 ** Insert an element "_e" at the head of the list "_l" 61 */ 62 #define PR_INSERT_LINK(_e,_l) PR_INSERT_AFTER(_e,_l) 63 64 /* Return the head/tail of the list */ 65 #define PR_LIST_HEAD(_l) (_l)->next 66 #define PR_LIST_TAIL(_l) (_l)->prev 67 68 /* 69 ** Remove the element "_e" from it's circular list. 70 */ 71 #define PR_REMOVE_LINK(_e) \ 72 PR_BEGIN_MACRO \ 73 (_e)->prev->next = (_e)->next; \ 74 (_e)->next->prev = (_e)->prev; \ 75 PR_END_MACRO 76 77 /* 78 ** Remove the element "_e" from it's circular list. Also initializes the 79 ** linkage. 80 */ 81 #define PR_REMOVE_AND_INIT_LINK(_e) \ 82 PR_BEGIN_MACRO \ 83 (_e)->prev->next = (_e)->next; \ 84 (_e)->next->prev = (_e)->prev; \ 85 (_e)->next = (_e); \ 86 (_e)->prev = (_e); \ 87 PR_END_MACRO 88 89 /* 90 ** Return non-zero if the given circular list "_l" is empty, zero if the 91 ** circular list is not empty 92 */ 93 #define PR_CLIST_IS_EMPTY(_l) \ 94 ((_l)->next == (_l)) 95 96 /* 97 ** Initialize a circular list 98 */ 99 #define PR_INIT_CLIST(_l) \ 100 PR_BEGIN_MACRO \ 101 (_l)->next = (_l); \ 102 (_l)->prev = (_l); \ 103 PR_END_MACRO 104 105 #define PR_INIT_STATIC_CLIST(_l) \ 106 {(_l), (_l)} 107 108 #endif /* prclist_h___ */ 109